Sleeve-type paperboard carriers are commonly used to package beverage containers. They are conventionally shipped to bottling facilities in the form of collapsed carrier sleeves which are opened to sleeve or tubular shape so that the open ends of the sleeves face outwardly during travel through a packaging machine. Beverage containers are then introduced to the sleeve through the open ends, after which the ends are closed by overlapping end flaps.
One type of carrier formed in this manner is adapted to carry conventionally shaped bottles having relatively long narrow necks. In order to tightly package the bottles the end panels of the cartons are formed so that they generally conform to the shape of the adjacent bottles, with the lower portion of the end panels extending vertically from the bottom panel and the upper portion of the end panels extending at an angle to the top panel so as to follow the tapered necks of the end bottles. To achieve this configuration the ends of the side panels of the carrier are shaped according to the particular end slope desired. Overlapping end flaps connected to the ends of the top and bottom panels are adhered to dust flaps which are connected along fold lines to the angled end edges of the side panels.
Although this arrangement produces a tightly bound package of beverage bottles, the angled design of the end panel is highly susceptible to misalignment of the flaps forming the end panel. A major cause of the problem is the tendency of the side panels to bow outwardly as the opened sleeve is pushed into the packaging machine, apparently due to the inability of the side panels to resist the vertical forces to which the sleeves are subjected during this operation. As a result, the carrier is not only slightly weakened, but its appearance can suffer greatly. Usually, a package of this type contains photographs, illustrations, legends or other indicia on the side panels. To present a unified appearance the overlapping end panel flaps must be precisely aligned so that the indicia on the end panels do not appear to be broken by the composite flaps. If the side panels are bowed at the time the flaps are adhered to the dust flaps and to each other, the resulting carrier will be out-of-square and the end panel indicia will exaggerate the flap misalignment. Because this is not consistent with the quality appearance desired of the package it is a problem that should be resolved. Prior to this invention, however, it did not appear possible to correct the situation without changing the basic sloped end panel shape or resorting to the use of thicker paperboard stock or expensive reinforced paperboard.
It is therefore an object of the invention to provide a sleeve-type carrier of the type described which does not have a tendency for the end panel flaps to be misaligned.